Purpose The purpose of this lab was to learn how to use the measuring equipment correctly, calculate volume and density of an object, express answers in significant figures, and calculate absolute error and percent error.
Hypothesis The accuracy of the measurements will be low but the Vernier caliper will be the most accurate tool for measuring.
Apparatus Card, meterstick, English-SI ruler, Vernier caliper, micrometer, set of density metal cylinders, balance and masses, several wooden blocks of various sizes, and several small spheres.
Procedure PART C
Pick a metal cylinder and measure its diameter and height three times. Record.
Calculate the volume of the cylinder. Record.
Find the mass of the cylinder and record it grams.
Repeat the above procedures for a second cylinder.
PART D
Measure the diameter of one of the spheres using a micrometer.
Find the mass of the sphere and record it.
Calculate the mass density of the sphere and then compare the answer to the accepted values.
Repeat the above procedures with a second sphere.
Data
PART C
Cylinder 1 Material: Plastic
Trial
Length L
Diameter D
Radius R
No.
Cm
Cm
Cm
1
9.71
1.64
0.82
2
9.71
1.64
0.82
3
9.71
1.64
0.82
Volume: 21 ml Mass: 22.289 g Experimental mass density: 1.1 Accepted mass density: 1.24 Error: 0.14 % Error: 11%
Cylinder 2 Material: Plastic
Trial
Length L
Diameter D
Radius R
No.
Cm
Cm
Cm
1
7.63
1.61
0.805
2
7.63
1.61
0.805
3
7.63
1.61
0.805
Volume: 15.5 ml Mass: 17.401 g Experimental mass density: 1.12 Accepted mass density: 1.24 Error: 0.12 % Error: 9.7%
PART D
Sphere 1 Material: Aluminum
Trial
Length L
Diameter D
Radius R
No.
Cm
Cm
Cm
1
2.515
2.515
1.258
2
2.515
2.515
1.258
3
2.515
2.515
1.258
Volume: 8.339 ml Mass: 20.062 g Experimental mass density: 2.406 Accepted mass density: 2.7 Error: 0.294 % Error: 11%
Sphere 2 Material: Glass
Trial
Length L
Diameter D
Radius R
No.
Cm
Cm
Cm
1
1.419
1.419
0.7095
2
1.419
1.419
0.7095
3
1.419
1.419
0.7095
Volume: 1.496 ml Mass: 3.049 g Experimental mass density: 2.038 Accepted mass density: 2.563 Error: 0.525 % Error: 20.5%
Analysis Equations Volume of a cylinder: (πr2L) π*0.82*9.71=21cm3 Mass density: (m/v) 22.289 g/21 cm3=1.1g/cm3 % Error: (Accepted mass density)-(experimental mass density)1.24-1.1 * 100%=11% (Accepted mass density) *100% 1.24 Volume of a sphere: (4/3 πr3) 4/3*π*(1.258 cm)3 = 8.339 cm3 After measuring the cylinders and spheres their volume formulas were used to find their volumes. Then they were weighed them so that those results could be used to find the experimental mass densities. After that the experimental mass densities and the accepted mass densities were used to find the percentage of error. The percent error ranged from 9.7% to 20.5% and mistakes made were most likely due to the micrometer and vernier caliper not being tightened enough around the object and misreading.
Conclusion The vernier caliper was more accurate than the micrometer but they both were very inaccurate because of mistakes made by the group (such as tightening and reading issues). More practice should be done using the measuring tools so that these mistakes are not made in future labs. In the results for sphere one there was 11% error and in the results for sphere two there was 20.5% error. A difference that may have affected the results was both that the glass marble may have had air bubbles and the micrometer when measuring the glass marble may not have been tight enough for fear of breaking and/or cracking the marble. In order to keep future results from having this much error, more practice should be done with the measuring tools and the students should go back over how to read them accurately.
The purpose of this lab was to learn how to use the measuring equipment correctly, calculate volume and density of an object, express answers in significant figures, and calculate absolute error and percent error.
Hypothesis
The accuracy of the measurements will be low but the Vernier caliper will be the most accurate tool for measuring.
Apparatus
Card, meterstick, English-SI ruler, Vernier caliper, micrometer, set of density metal cylinders, balance and masses, several wooden blocks of various sizes, and several small spheres.
Procedure
PART C
PART D
Data
PART C
Cylinder 1 Material: Plastic
Mass: 22.289 g
Experimental mass density: 1.1
Accepted mass density: 1.24
Error: 0.14
% Error: 11%
Cylinder 2 Material: Plastic
Mass: 17.401 g
Experimental mass density: 1.12
Accepted mass density: 1.24
Error: 0.12
% Error: 9.7%
PART D
Sphere 1 Material: Aluminum
Mass: 20.062 g
Experimental mass density: 2.406
Accepted mass density: 2.7
Error: 0.294
% Error: 11%
Sphere 2 Material: Glass
Mass: 3.049 g
Experimental mass density: 2.038
Accepted mass density: 2.563
Error: 0.525
% Error: 20.5%
Analysis
Equations
Volume of a cylinder: (πr2L) π*0.82*9.71=21cm3
Mass density: (m/v) 22.289 g/21 cm3=1.1g/cm3
% Error: (Accepted mass density)-(experimental mass density) 1.24-1.1 * 100%=11%
(Accepted mass density) *100% 1.24
Volume of a sphere: (4/3 πr3) 4/3*π*(1.258 cm)3 = 8.339 cm3
After measuring the cylinders and spheres their volume formulas were used to find their volumes. Then they were weighed them so that those results could be used to find the experimental mass densities. After that the experimental mass densities and the accepted mass densities were used to find the percentage of error. The percent error ranged from 9.7% to 20.5% and mistakes made were most likely due to the micrometer and vernier caliper not being tightened enough around the object and misreading.
Conclusion
The vernier caliper was more accurate than the micrometer but they both were very inaccurate because of mistakes made by the group (such as tightening and reading issues). More practice should be done using the measuring tools so that these mistakes are not made in future labs. In the results for sphere one there was 11% error and in the results for sphere two there was 20.5% error. A difference that may have affected the results was both that the glass marble may have had air bubbles and the micrometer when measuring the glass marble may not have been tight enough for fear of breaking and/or cracking the marble. In order to keep future results from having this much error, more practice should be done with the measuring tools and the students should go back over how to read them accurately.